Ed Sirett wrote:
Hi all,

This week I put a 31kW Vaillant Condensing Combi in. The other month I put
in a 24kW unit. As I was doing the job, I started to think is there
_anything_ in the boiler that's different between the two units? I had
sort of assumed they would be _almost_ identical but with perhaps a bigger
fan, gas valve or burner/heatX.

Well I was showing my apprentice how you could find out about all the
different settings.
We looked up the fan speed when it was doing HW and it was 499 rpm, I was
fairly sure when I commissioned the 24kW unit the fan speed was 395 on HW.
snip
I suppose some people would say buy a 30kW boiler from someone else who
could potentially be cheaper for the higher powered models.

In Hong Kong there is probably someone who sells grey market chip upgrades...

But are they CORGI registered?